Telescoping rod antenna with radial arm ground plane



R. T. RHEIN TELESCOPING ROD. ANTENNA WITH RADIAL ARM GROUND PLANE Filed Sept 9, 1968 ATTORA/[Y United States Patent 3,541,558 TELESCOPIN G ROD ANTENNA WITH RADIAL ARM GROUND PLANE Raymond T. Rhein, 2621 Old Welsh Road, Willow Grove, Pa. 19090 Filed Sept. 9, 1968, Ser. No. 758,505 Int. Cl. H01q 1/10, 1/32, 9/00 US. Cl. 343749 4 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION Field of the invention This invention relates to antennas for radio reception.

Description of the prior art Various arrangements of antennas have heretofore been proposed but these have had various shortcomings including undesired signal noise ratio, rain noise, failure under wind stress, and tendency to lightning damage.

SUMMARY OF THE INVENTION In accordance with the invention an antenna is provided particularly suited for five-eighths wave length, in which the components are constructed and assembled so as to be rigid and free from relative movement, and with improved electrical contact which includes a vertical element and a plurality of radial elements, six being preferred. The vertical and radial elements are of relatively light weight material such as aluminum with joints which are strong and rigid and prevent relative movement between respective parts.

It is the principal object of the present invention to provide an antenna which is simple in construction, light in weight, but with enhanced rigidity and freedom from movement at the joints thereof and with which the greatest possible gain is achieved together with improvement in operating qualities.

It is a further object of the present invention to provide an antenna of the character aforesaid which can be readily assembled and installed, and which will have a long useful life.

Other objects and advantageous features of the invention will be apparent from the description and claims.

BRIEF DESCRIPTION OF THE DRAWING The nature and characteristic features of the invention will be more readily understood from the following description taken in connection with the accompanying drawings forming part thereof, in which:

FIG. 1 is a view in elevation of an antenna in accordance with the invention;

FIG. 2 is a vertical central sectional view, parts being broken away to reduce the height and width of the figure; and

FIG. 3 is a fragmentary horizontal sectional view taken approximately on the line 33 of FIG. 2.

It should, of course, be understood that the description and drawings herein are illustrative merely, and that various modifications and changes can be made in the strucice ture disclosed without departing from the spirit of the invention.

Like numerals refer to like parts throughout the several views.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now more particularly to the drawings, the antenna in accordance with the invention comprises a base with a vertical hollow metallic tube 11 having a collar 12 carrying a set screw 13 for mounting on a mast (not shown) such as a one inch mast.

The tube 11 is preferably exteriorly grounded.

At the upper end of the tube 11 a closely fitting metallic supporting sleeve 15 is provided held in place by a set screw 16 and provided with a plurality of radial openings 17 within which radial arms 18, preferably metallic rods or tubes, are secured. In a specific embodiment six radial arms 18 of a length of fifty-four inches are employed.

The sleeve 15 has a shoulder 20 at the upper end thereof for the reception of a sleeve 21 of electrical nonconducting material such as a synthetic resin of the phenolic type.

At the upper end of the sleeve 21 a closure collar 22 is provided with a shoulder 23 engaging the sleeve 21. The collar 22 is secured to a vertical metallic tube 24 which, at its upper end, has a metallic mast tube 25 engaged therein in an overlapped or telescoped relation and secured against vertical movement by screws 26.

The tube 25 provides the lower part of a vertical mast which is constructed in a manner to be explained.

The tube 25 in a particular embodiment is ten feet in length and at its upper end has a metallic bushing 27 engaged therein with a close fit. The bushing 27 has a shoulder 28 engaging the upper end of the tube 25 and in the interior thereof, in closely fitting relation has the lower end of a mast tube 29. The mast tubes 25 and 29 are held against separation and vertical movement by a plurality of set screws 30. In the specific embodiment referred to the tube 29 has a length of ten feet.

The mast tube 29, at its upper end has a metallic bushing 31 in tight engagement therein with a shoulder 32 engaging the upper end of the tube 29.

The bushing 31 has in tight engagement therein an uppermost metallic mast tube 35, the tubes 29 and 35 being held against separation and vertical movement by set screws 36. The upper end of the tube 35 is closed by an end closure 37. In the particular embodiment referred to above the tube 35 can be of a length of four and onehalf feet.

In overlapping relation with the ends of the tubes 11 and 24 a core is provided, preferably of electrical nonconducting material such as a synthetic resin of the phenolic type.

The core 40 has a central opening 41 and on the extension thereof, between the ends of the tubes 11 and 24 has a helical groove thereon for the turns of a winding 42 of insulated wire.

In the specific embodiment ten turns of 14 gage enameled wire on a core 40 with an outside diameter of one and three-eighths inches has been found satisfactory. The winding 42 may be secured at its ends in any desired manner such as by clips 43.

The space 44 surrounding the winding 42 and between the tubes 11 and 24, and sleeve 15 and collar 22 and within the sleeve 21 is preferably filled with an inert insulating material and moisture resistant material such as a hard wax.

The winding 42 has a tap 45 therefrom which is connected to the central contact of a conventional connector 46 to which the lead-in, such as a coaxial cable is connected.

The tube 11 is preferably connected by a conductor 47 to the outside of the connector 46.

The antenna heretofore described develops high gain, in excess of db omidirectional gain and 6.4 db in measured field strength intensity. Improvement in the signal noise ratio is of 6 to 20 db. Rain noise also is eliminated. The construction of the tubes 11, 24, 25, 29 and 35 and sleeve of aluminum tubing and the collar 22, bushing 27 and bushing 31 of aluminum and the tight fitting of the parts in engagement with retention by positive fasteners all are believed to contribute to the strength, weather resistance and improved antenna action.

The mounting and enclosing of the winding 42 also enhances the weather resistant character of the antenna.

I claim:

1. An antenna comprising:

a vertical tubular base member having a conductive metallic sleeve exteriorly disposed thereon at the upper end thereof,

a plurality of horizontal arms extending radially outwardly with respect to said sleeve,

a core member in partially telescoped and in engaging relation to said base member and extending upwardly from said base member and having a coil carried thereby,

an insulating sleeve in surrounding and enclosing relation to said core member,

said insulating sleeve being engaged in and supported by said conductive sleeve,

a mast having said core member in partially telescoped relation thereto and extending upwardly from said core member, and

a closure collar engaged with said insulating sleeve and said mast,

said mast comprising a plurality of elongated tubular members of different diameters and in a series having tubular bushings interposed between their meeting ends,

said tubular bushings and tubular members being in contacting engagement along their meeting portions.

2. An antenna as defined in claim 1 in which:

said tubular bushings each has a shoulder with which one of said tubular members is in engagement,

the other of said tubular members having an end in concentric secured relation to the contiguous end of another tubular member.

3. An antenna as defined in claim 1 in which:

said mast is insulated from said coil by said core.

4. An antenna as defined in claim 1 in which:

said mast and said coil are insulated from said base by said core.

References Cited UNITED STATES PATENTS 2,026,652 1/1936 Ponte 343-834 2,674,693 4/1954 Millett et al 343-834 2,875,443 2/1959 Kandoian 343-723 X 2,944,257 7/1960 Martin 343-749 3,172,109 3/1965 Senrui 343-749 3,268,897 8/1966 Link 343-749 OTHER REFERENCES Dr. A. R. Von Hippel, Dielectric Materials and Applications; MIT Press: Cambridge; pp. 291-293, 294 and 357.

ELI LIEBERMAN, Primary Examiner T. VEZEAU, Assistant Examiner US. Cl. X.-R. 343-848, 901 

